Yes sorry I was using it wrong. Here’s the trace after the segfault:
(gdb) thread apply all bt
Thread 4 (Thread 15525.15625):
#0 0x00007f1674b1acb9 in poll () from target:/lib/x86_64-linux-gnu/libc.so.6
#1 0x00007f166080e5c9 in ?? () from target:/snap/tablexplore/x1/kf5/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2 0x00007f166080e6dc in g_main_context_iteration () from target:/snap/tablexplore/x1/kf5/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3 0x00007f1663c321cc in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Core.so.5
#4 0x00007f1663bd521a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Core.so.5
#5 0x00007f16639eb844 in QThread::exec() () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Core.so.5
#6 0x00007f1657d1ffd5 in QDBusConnectionManager::run() () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5DBus.so.5
#7 0x00007f16639ecb35 in QThreadPrivate::start(void*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Core.so.5
#8 0x00007f16747ee6db in start_thread () from target:/lib/x86_64-linux-gnu/libpthread.so.0
#9 0x00007f1674b2771f in clone () from target:/lib/x86_64-linux-gnu/libc.so.6
Thread 3 (Thread 15525.15624):
#0 0x00007f16747f4fb9 in pthread_cond_timedwait@@GLIBC_2.3.2 () from target:/lib/x86_64-linux-gnu/libpthread.so.0
#1 0x00007f16639f35a4 in QWaitCondition::wait(QMutex*, QDeadlineTimer) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Core.so.5
#2 0x00007f16639f08d1 in QThreadPoolThread::run() () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Core.so.5
#3 0x00007f16639ecb35 in QThreadPrivate::start(void*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Core.so.5
#4 0x00007f16747ee6db in start_thread () from target:/lib/x86_64-linux-gnu/libpthread.so.0
#5 0x00007f1674b2771f in clone () from target:/lib/x86_64-linux-gnu/libc.so.6
Thread 2 (Thread 15525.15623):
#0 0x00007f1674b1acb9 in poll () from target:/lib/x86_64-linux-gnu/libc.so.6
#1 0x00007f165d6b6747 in ?? () from target:/snap/tablexplore/x1/usr/lib/x86_64-linux-gnu/libxcb.so.1
#2 0x00007f165d6b836a in xcb_wait_for_event () from target:/snap/tablexplore/x1/usr/lib/x86_64-linux-gnu/libxcb.so.1
#3 0x00007f16584f37b0 in QXcbEventQueue::run() () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5XcbQpa.so.5
#4 0x00007f16639ecb35 in QThreadPrivate::start(void*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Core.so.5
#5 0x00007f16747ee6db in start_thread () from target:/lib/x86_64-linux-gnu/libpthread.so.0
#6 0x00007f1674b2771f in clone () from target:/lib/x86_64-linux-gnu/libc.so.6
Thread 1 (Thread 15525.15525):
#0 0x00007f1674ab7426 in ?? () from target:/lib/x86_64-linux-gnu/libc.so.6
#1 0x00007f164f9e9138 in ?? () from target:/snap/tablexplore/x1/kf5/usr/lib/x86_64-linux-gnu/qt5/plugins/platformthemes/libqxdgdesktopportal.so
#2 0x00007f164f9e9bf0 in ?? () from target:/snap/tablexplore/x1/kf5/usr/lib/x86_64-linux-gnu/qt5/plugins/platformthemes/libqxdgdesktopportal.so
#3 0x00007f165c0140d0 in QDialogPrivate::setNativeDialogVisible(bool) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#4 0x00007f165c025eb2 in QFileDialog::setVisible(bool) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#5 0x00007f165c014ef1 in QDialog::exec() () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#6 0x00007f165c027361 in QFileDialog::getSaveFileUrl(QWidget*, QString const&, QUrl const&, QString const&, QString*, QFlags<QFileDialog::Option>, QStringList const&) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#7 0x00007f165c0274bf in QFileDialog::getSaveFileName(QWidget*, QString const&, QString const&, QString const&, QString*, QFlags<QFileDialog::Option>) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#8 0x00007f165c782a9f in Sbk_QFileDialogFunc_getSaveFileName () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/QtWidgets.abi3.so
#9 0x000000000050a4a5 in ?? ()
#10 0x000000000050cc96 in _PyEval_EvalFrameDefault ()
#11 0x00000000005095c8 in ?? ()
#12 0x000000000050a2fd in ?? ()
#13 0x000000000050beb4 in _PyEval_EvalFrameDefault ()
#14 0x0000000000507be4 in ?? ()
#15 0x0000000000509900 in ?? ()
#16 0x000000000050a2fd in ?? ()
#17 0x000000000050beb4 in _PyEval_EvalFrameDefault ()
#18 0x0000000000507be4 in ?? ()
#19 0x0000000000588c8b in ?? ()
#20 0x000000000059fd0e in PyObject_Call ()
#21 0x00007f1664142d2f in PySide::SignalManager::callPythonMetaMethod(QMetaMethod const&, void**, _object*, bool) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/libpyside2.abi3.so.5.15
#22 0x00007f1664147cdf in PySide::GlobalReceiverV2::qt_metacall(QMetaObject::Call, int, void**) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/libpyside2.abi3.so.5.15
#23 0x00007f1663c0ef97 in void doActivate<false>(QObject*, int, void**) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Core.so.5
#24 0x00007f165be26672 in QAction::triggered(bool) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#25 0x00007f165be28a9e in QAction::activate(QAction::ActionEvent) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#26 0x00007f165bf19a78 in QAbstractButtonPrivate::click() () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#27 0x00007f165bf19b95 in QAbstractButton::mouseReleaseEvent(QMouseEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#28 0x00007f165bffca8a in QToolButton::mouseReleaseEvent(QMouseEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#29 0x00007f165be6a740 in QWidget::event(QEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#30 0x00007f165bffcb59 in QToolButton::event(QEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#31 0x00007f165be2c43c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#32 0x00007f165be331f8 in QApplication::notify(QObject*, QEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#33 0x00007f165c6c2325 in QApplicationWrapper::notify(QObject*, QEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/QtWidgets.abi3.so
#34 0x00007f1663bd6808 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Core.so.5
#35 0x00007f165be3253a in QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool, bool) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#36 0x00007f165be83fe8 in QWidgetWindow::handleMouseEvent(QMouseEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#37 0x00007f165be86cf3 in QWidgetWindow::event(QEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#38 0x00007f165be2c43c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#39 0x00007f165be32f20 in QApplication::notify(QObject*, QEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Widgets.so.5
#40 0x00007f165c6c2325 in QApplicationWrapper::notify(QObject*, QEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/QtWidgets.abi3.so
#41 0x00007f1663bd6808 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Core.so.5
#42 0x00007f165e4ed56d in QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::MouseEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Gui.so.5
#43 0x00007f165e4ee955 in QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Gui.so.5
#44 0x00007f165e4ca8ab in QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Gui.so.5
#45 0x00007f16584f469a in xcbSourceDispatch(_GSource*, int (*)(void*), void*) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5XcbQpa.so.5
#46 0x00007f166080e417 in g_main_context_dispatch () from target:/snap/tablexplore/x1/kf5/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#47 0x00007f166080e650 in ?? () from target:/snap/tablexplore/x1/kf5/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#48 0x00007f166080e6dc in g_main_context_iteration () from target:/snap/tablexplore/x1/kf5/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#49 0x00007f1663c321cc in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Core.so.5
#50 0x00007f1663bd521a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Core.so.5
#51 0x00007f1663bde1d3 in QCoreApplication::exec() () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/Qt/lib/libQt5Core.so.5
#52 0x00007f165c6bfd98 in Sbk_QApplicationFunc_exec_ () from target:/snap/tablexplore/x1/lib/python3.6/site-packages/PySide2/QtWidgets.abi3.so
#53 0x000000000050a461 in ?? ()
#54 0x000000000050beb4 in _PyEval_EvalFrameDefault ()
#55 0x00000000005095c8 in ?? ()
#56 0x000000000050a2fd in ?? ()
#57 0x000000000050beb4 in _PyEval_EvalFrameDefault ()
#58 0x0000000000507be4 in ?? ()
#59 0x000000000050ad03 in PyEval_EvalCode ()
#60 0x0000000000634e72 in ?? ()
#61 0x0000000000634f27 in PyRun_FileExFlags ()
#62 0x00000000006386df in PyRun_SimpleFileExFlags ()
#63 0x0000000000639281 in Py_Main ()
#64 0x00000000004b0dc0 in main ()